<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        .toptip .jie{
            visibility: hidden;

        }
        .toptip:hover .jie{
            visibility: visible;
        }
    </style>
</head>
<body>
    <div class="toptip">移到我上面
        <span class="jie">toptop</span>
    </div>
    
</body>
</html>